<!DOCTYPE html>
<html lang="en" xmlns:v-bind="http://www.w3.org/1999/xhtml">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
</head>
<body>
<!--v-bind 用于 class 和 style 时做了专门的增强-->
<div id="app15">
    <div v-bind:class="{ active: isActive }">666</div>
    <div v-bind:class="[activeClass]">777</div>
</div>

<script type="text/javascript">
    var app = new Vue({
        el: '#app15',
        data: {
            isActive: true,
            activeClass: 'active',
        }
    })
</script>

<style type="text/css">
    .active {
        color: paleturquoise;
    }
</style>
</body>
</html>